In the past, there has been various types of boiler systems that have been used to provide heat to commercial and residential buildings. One of the main types is a closed-loop system. A closed-loop system includes a pressure vessel that is used to generate the steam that is later employed to effect heating. In the simplest form, a closed-loop system will have a steam outlet that will provide steam to the apartments or floors of a commercial building, or the rooms of a residence. The steam is provided to a heat exchanger of some type, such as a radiator, convector, baseboard unit, radiant panel, or a fan-driven heater. Once the heat is removed from the steam, it will condense and be returned to the pressure vessel where the cycle will be repeated. The condensate that is formed becomes the feedwater that will be used for the continued generation of steam.
The essentials of steam generation are to have a furnace for the combustion of fuel for the release of heat, a pressure vessel in which the boiler feedwater is raised to the boiling temperature, evaporated into steam, and, if desired, superheated beyond the saturation temperature, and an outlet for the steam. The pressure vessel also has a connection to a line that provides make-up feedwater that replaces the feedwater that is lost. All systems lose some amounts of feedwater in operation that has to be replaced. If it is not replaced, eventually the pressure vessel will run dry and be damaged. There are a number of methods to ensure that this does not happen, including, but not limited to, feedwater level sensors, sight tubes, and the like.
The general boiler system that has been discussed may serve as the basis of a heating system for a commercial or residential building, or it may be part of a heating and cooling system of such buildings. Since the types of systems just discussed are closed-loop systems, the hot water that is part of the boiler feedwater/steam thermocycle is not available for use as a hot water supply to the commercial or residential buildings. Hot water for this purpose has to be supplied by another source.
Hot water that is to be supplied to commercial or residential buildings may be generated in a number of ways. For example, there can be single hot water heaters for apartments (or houses) or there can a central hot water generating station that will supply all of the hot water needs. It has been found, however, that it may not be practical to have individual hot water heaters in each apartment. Moreover, even in residential housing, the desire may not be to have an individual hot water heater because of the space needed to house it. In these cases, some type of centralized system that can make use of the boiler heating or heating/cooling system to provide hot water without affecting the feedwater or condensate that exist in the boiler system is described.
One method of providing hot water that uses the boiler system without affecting the feedwater is to have a coil of tubular material passing inside the pressure vessel. The tubular material is preferably a coil of copper tubing that has an inlet that receives water from the feed line and an outlet that provides hot water that may be used as a hot water supply for a commercial or residential building. Within the pressure vessel, the exterior surface of the coil of copper tubing may be exposed to the feedwater only, steam only, or both.
As the water fed into the inlet of the copper tubing progresses to the outlet, heat is transferred from the feedwater or steam to the copper tubing, which in turn, transfers the heat to water in the copper tubing. The temperature of the water leaving at the outlet of the copper tubing will depend on the amount of heat transferred to the water.
In the past, there has been separate lines to supply make-up feed water to the pressure vessel and to supply water for input to the coil of copper tubing. Moreover, there was yet another line that was used to provide cold water to the commercial or residential building. Moreover, there also was difficulty in obtaining hot water at the proper temperature for use in commercial or residential building as output from the outlet of the copper tubing. There also was a need for an additional mixing system to control the temperature of the hot water. This mixing system required its own source of cold water that would be used to mix with the hot water.
There have been various types of manifolds that have been used for handling water and, in some cases, hot water. These manifolds have been associated with faucets, shower heads, tub-shower diverters, heating supply systems, and water valve assemblies to name a few. Although, some of these manifolds have multiple outputs, they were not associated with a boiler system such that it will receive a single feed input, and supply make-up feedwater to the pressure vessel, supply water for the copper tubing for heating, and supply water for mixing with the output from the copper tubing outlet to obtain hot water in the desired temperature range. Moreover, these manifolds were not operated to maintain the pressure in the manifold at a desired level. It would be desirable to have a manifold with these features.